Well, I'm admittedly clueless, but the only way to know for sure if your mixture is safe is to measure the air/fuel ratio with the car on the dyno (well, you could do it on the street, I suppose, but what a p.i.t.a.). I've read about turbo setups that used the stock PCM with bigger injectors and a recalibrated MAF, but I don't understand how it worked since the PCM will try to adapt and run a stoichiometric air/fuel ratio. That setup fed boost pressure to the pressure transducer in the fuel rail in order to raise the fuel pressure as the boost rises, but I never did understand why the PCM wouldn't just pulse the injectors for shorter durations to lean out the mixture.

So I guess you'll need a chip. I don't know what it costs to have one programmed, but my gut says $500 will definitely cover it.

As for the off-road pipe making the mixture rich, HUH?
I don't know much about this stuff, buy why would an off-road pipe enrich the mixture? I thought the oxygen sensor AFTER the cat was just used to check the cat's efficiency, while the first oxygen sensor is what the PCM uses to tell how rich or lean the mixture is. So your first oxygen sensor should still be doing what it was doing before the off-road pipe. Did you do something goofy with one of those O2 cheaters? I'm confused. Again.

I dont realy feel like replacing it, since my car runs fine. I was just informed that a offroad pipe, because of dimensions compared to a restrictive cat, makes your engine run "richer"...but again this is what I was told.

Im not a mechanic myself, hehe, just trying to understand my car and how to make everything run smoothly

Hehe, I can relate. Everybody else will tell you this, but I'll go first - be REALLY careful with this! Running any turbo without good fuel management is arguably one of the quickest ways to destroy your engine. I'm checking out turbo kits myself, and the first question I always ask is "what exactly does your kit include for fuel management?". For me, it's the highest priority.

Oh hey, I just realized you're in California - aren't you gonna be up shit creek when it's time for an inspection? (The second question I always ask is if the kit bolts onto the stock cat.)

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